St George Mining Ltd (ASX:SGQ) has ended its 2022 drilling campaign at the Mt Alexander Project in WA’s Goldfields with more positive assays from the Jailbreak Prospect, confirming that lithium-bearing pegmatite outcrops cover 20 square kilometres.
Some 79 rock chip samples from Exploration Licence 29/638 - 75% owned by St George and the remainder by IGO Ltd - returned assays with anomalous lithium values and pathfinder elements along an unexplored 5-kilometre strike of the pegmatite corridor.
With these results, the company has completed its first-ever lithium drilling at Mt Alexander, where rock chip samples have returned assays up to 3.25% Li2O.
In total, 23 reverse circulation (RC) and diamond drill holes for 2,409 metres were completed. Of those, 20 drill holes intersected pegmatites with visual lithium-bearing minerals.
Importantly, drilling indicates the pegmatites continue below surface up to a vertical depth of at least 200 metres and remain open in most cases.
Plan view map against interpreted geology showing drill hole locations from current program.
Maiden lithium hunt
St George Mining’s executive chairman John Prineas said: “Our first-ever lithium-targeted drilling at Mt Alexander was designed as an initial program to test for continuity below surface of the high-grade lithium-bearing pegmatite outcrops confirmed by rock chip sampling.
“The drill program has successfully confirmed that these pegmatites continue below surface - in some cases up to 200 metres below surface. Lithium-bearing minerals have been logged in these pegmatite intersections with assays pending.
“These results continue to indicate the potential for a large lithium-bearing pegmatite mineral system at Mt Alexander, the full scope of which is still evolving as we continue work across the project.
“This is a great start to our lithium drilling campaign at Mt Alexander and we are excited about ramping up drilling and broader exploration activities in 2023 with more than 20,000 metres of drilling scheduled.
“There has been no previous systematic lithium exploration at Mt Alexander and we are delighted with the results of our work programs so far, which have quickly provided walk-up drill targets and confirmation of high-grade mineralisation starting from surface.
“With more than 13 kilometres of the pegmatite corridor yet to be effectively explored - and ongoing rock chip sampling confirming other areas of additional prospective pegmatites - we believe the exploration upside at Mt Alexander is significant.
“Importantly, the success of the drill program means we end 2022 with significant momentum that will carry through into the New Year, with plans to resume drilling in as early as February.”
Diamond drill core which intersected 5 metres of pegmatites from 49.5 metres downhole.
Nickel targets
Drilling also tested for nickel targets, although no apparent nickel sulphide mineralisation was found in the intersected sulphides.
Nevertheless, the massive and semi-massive sulphides have been sampled and will be submitted for assaying to test for base metal mineralisation and/or pathfinder elements.
These drill holes have also been cased, with downhole electromagnetic surveys in progress to investigate for the potential of conductive bodies around the drill holes.
Busy period ahead
St George intends to begin 2023 with an aggressive work program.
The following activities are either ongoing or being planned:
- Assays for soil surveys at E29/962, which are pending, have the potential to identify a lithium signature in an area where pegmatites are not exposed due to thin cover.
- Assays for completed rock chip sampling of pegmatites in other parts of the pegmatite field are pending with more than 92 samples submitted for assay.
- Assays are pending for all the recently completed RC and diamond drilling.
- Field mapping and rock chip sampling will resume in January, with more than 13 kilometres of the pegmatite corridor to explore.
- Lithium-bearing pegmatite outcrop has been visually identified in these areas and a systematic sampling program is required to further assess prospectivity and potential drill targets. These areas include the recently acquired P29/2680 and E29/1143, both 100% owned by St George.
- Major lithium drill program to commence in February 2023 with more than 20,000 metres of drilling scheduled for H1 2023 with potential to escalate.